Trench-brace.



v PATENTED MAY 5, 1908. M. R. DE FRANCE & A. E. READ.

TRENGH BRAGE.

APPLICATION FILED FEB. 14, 1908.

UNITED STATES PATENT @FFTQE.

MURRELL R. DE FRANCE AND ALBERT E. READ, OF BELLEVUE, PENNSYLVANIA.

TRENCH-IB RA CE To all whom it may concern:

Be it known that we, MURRELL R. DE FRANCE and ALBERT E. READ, residentsof Bellevue, in the county of Allegheny and State of Pennsylvania, haveinvented certain new and useful Improvements in Trench- Braces, of whichthe following is a specification.

Extensible trench braces, used to prevent excavations from caving in,are subjected to very rough usage. The parts .most frequently damagedare the bearing shoes, and more particularly the devices which looselyconfine the shoes on the brace ends. \Vorkmen do not ordinarily exercisecare in having the shoes directly opposite each other when placing thebrace, the general practice being to straighten them up with a sledgehammer after they have been expanded within the trench. This sledging isdisastrous to the shoes, and particularly to the devices heretoforeemployed for loosely uniting the shoes and brace arms.

The primary object of this invention is to provide a shoe and securingmeans of such form as to withstand this rough usage, and at the sametime afford an efficient connection and bearing. To this end, we so formthe shoe as to completely embrace all portions of the securing device aswell as the whole of the bearing end of the arm and thus effectuallyprotect them from the sledgehammer blows. The shoes are of suchsubstantial construction as not to be injured thereby.

In the accompanying drawings Figure 1 is an elevation of the brace inoperative position. Fig. 2 is a vertical sectionalview. Fig. 3 is ahorizontal cross-section. Fig. 4 is an inner face view of one of theshoes with the arm securing device in position and with the arm shown insection on line 4-4 of Fig. 2. Fig. 5 is a similar view of one of theshoes with the'brace arm and arm securing means removed.

The telescoping portions of the brace arms are of well knownconstruction, 2 being the tubular arm, and 3 the threaded arm whichmoves freely therein, with the usual lever nut 4 operating on arm 3 andbearing against the extremity of arm 2 for expanding the brace. Tubulararm 2 detachably connects at 5 with head 6 which forms the end bearingfor that arm. The exterior of head 6 which cooperates with its shoe isof exactly the same formation as head 7 forming the in- Specification ofLetters Patent.

Application filed February 14, 1908.

Patented May 5, 1908.

Serial No. 415,841.

tegral outer end of arm 3, and the shoes and shoe-securing means are oflike construction at each end of the brace.

Each of the shoes 9, which bears against the shoring or temporary lining8 of the excavation, is of general rectangular form and recessed on itsinner face, the end portions of the recess being shallower than the intermediate portion to form faces 10. WVithin the central deeper portionof the recess in the partially spherical bearing socket 11, and fittingthe same is the similarly formed extremity 12 of arm-head 6 or 7, as thecase may be. The spherical surface of extremity 12 is of larger areathan the socket so that the brace arm may have limited angular movementin any direction.

For loosely uniting the shoes and arms, heads 6 and 7 are formed eachwith a shoulder or enlargement 13 adjacent to the rounded extremity 12,and inwardly from this shoulder the head is of irregular section, havinga longer diameter or greater thickness in one direction than in thedirection at right angles thereto, as indicated at 14, the sectionsomewhat resembling an oval, as clearly shown in Fig. 4. Embracing thisortion of the head is securing plate 15 which iits wholly within thehead recess and at its opposite ends bears against faces where it issecured by bolts 16. This plate is completely surrounded by the rim-likeinner portion 9 of the shoe, and hence it is fully protected on allsides.

Passage 17 through plate is oval in shape and is larger than theirregular head section extending therethrough, thereby af fording thebrace-arm limited. angular movement in any direction. But as the longerdiameter of the head section 14 is greater than the width of passage 17,the arm is prevented from making a complete rotation, which if permittedwould obviously interfere with the expansion of the brace effected bylever nut 1. Shoulder 13 is too large to pass through opening 17, thuspreventing the parts from separating.

The central portion of plate 15 is bulged or 'bellied outwardly at 15 toafiord sufficient room for the turning of shoulder 13, the face of theshoulder bearing against the plate, being rounded as indicated at 13, tofacilitate the angular movement of the arm in its shoe bearing. Rim 9 ofthe shoe is enlarged at 9 to protect the bulged portion 15 of the plate.

In practice, it frequently happens that the shoes are not alined wheninserting the brace, or they may be moved out of line by slip ing of thebrace or the shoring. While the exibility of the joints compensates forthis without straining or injuring the brace, it is of course desirableto have the shoes directly opposite each other, so they are usuallydriven into alinement with a sledge hammer or similar tool. Ourinvention is designed especially to withstand this rough usage. Theshoes are so formed as not to be injured by the sledging, regardless ofthe side or end struck, and as they completely inclose the securingmeans the latter is fully protected. Many braces of the types now in useare broken and destroyed simply because the securing means or joints areexposed, and being close to the shoes receive the destructive blowsintended for the latter.

While we have here shown, described, and claimed the improvement as atrench brace, it will be understood that the device may be used in anyand all forms of jacking or supporting operations where such animplement may be employed.

1. In a trench brace, the combination of a shoe recessed on its innerface, a brace arm bearing in the recess, a plate-like securing deviceentered and secured wholly within the shoe recess, said plate-likedevice having a passage for the brace-arm, and a shoulder on the armwithin the shoe recess and back of the plate-like device and preventingoutward movement of thearm.

2. In a trench brace, the combination of a shoe, a brace arm bearing atits end against the shoe, a portion of the arm near its end beingnon-circular in cross-section with a shoulder between saidcross-sectional portion and the bearing end, and an arm-holding plateembracing the non-circular portion of the arm and secured to the shoe,the arm passage through the plate being larger than the non-circular armsection and of such shape as V to prevent complete rotation of the armwithout interfering with the angular movement of the latter.

3. In a trench brace, the combination of a shoe, a brace arm bearing atits end against the shoe, a portion of the arm near its end having across-sectional shape of reater length than width with a shoulder on t earm between said portion and its bearing end, a plate embracing saidcross-sectional portion of the arm and secured to the shoe, the armpassage through the plate being of oval shape and of a size to affordthe arm angular movement but holdingit against complete rotation, thearm shoulder preventing movement of the bearing end of the arm outwardlythrough the plate passage.

4. In a trench brace, the combination of a shoe recessed on its innerface and within said recess formed with a bearing socket, a brace armhaving a rounded extremity adapted'to bear in said socket, the armhaving a shoulder adjacent its rounded end, the arm inwardly from theshoulder being of substantially oval section, and a plate secured whollywithin the shoe recess and having an oval passage through which the armextends, said passage being larger than the oval-like section of the armand embracing the arm in the plane of said section, the width of theoval passage being less than the longer diameter of the oval-likesection of the arm to prevent complete rotation of the latter.

5. In a trench brace, the combination of a shoe recessed on its innerface, the central portion of the recess being deeper than its ends, abrace arm bearing in the central part of the recess, a plate enteredwholly within the recess and secured to the inner faces of the shallowend portions thereof, the plate having a passage through which the bracearm extends, and a shoulder on the arm within the recess and back of theplate for engaging the latter and preventing outward movement of thearm.

In testimony whereof We aflix our signatures in presence of twowitnesses.

MURRELL R. DE FRANCE. ALBERT E. READ. Witnesses:

JNo. J. FITZGERALD, J. M. NESBIT.

